2 

Seconds that pass until another American needs a transfusion

4,500,000 

Number of American lives saved each year by transfusions

48 

Gallons of blood an American could donate if she began giving at age 17 and gave every 56 days until reaching age 76

5 

Estimated annual percentage of eligible Americans who donate

500,000 

Number of Americans who donated in the days following the September 11 attacks

29,000,000 

Number of units of blood components transfused in 2001 (a single donation can be divided into plasma, platelets and red blood cells)

2 

Times as likely heart patients are to die after a transfusion to treat blood loss or anemia as heart patients who do not receive a transfusion, possibly because of such problems as artery disease aggravated by the transfusion.